Find Difference between 2 Tables, 22 GB each, on unique key

Need to get=A0the difference records between 2 tables each of size 22GB =
(each containing 32 Million rows). The temp tablespace is 30GB.

Unique index exists on the respective fieldname on which to check for =
difference.

Which approach faster/most efficient way?

Select <fieldname> from Table 1 MINUS Select <fieldname> from Table =
2? - If so what would be the consumption of TEMP Tablespace? =
Additionally how to=20

some Other SQL script=20

PL/SQL script

Will doing a FULL index ONLY Scan be faster than a FULL Table scan?

=A0

Machine configuration - 4 cpu's and 1GB DIMM RAM.=20
OS version - Unix Sun Solaris machine Version not known.
Oracle version -=A0 8.1
Nature of application -=A0Joins and inserts
production issue -=A0 Yes
Tables being accessed by other applications - YES, during certain time =
slot. We have abt 12-14hrs when they are not touched by any application.
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